Trimming device for post sewing machines



April 6, 1965 K. KLEEMANN ETAL 3,176,639

TRIMMING DEVICE FOR POST SEWING MACHINES 2 Sheets-Sheet l Filed June 27,1962 illvfilllllll,

April 6, 1965 K. KLEEMANN ETAL 3,176,639

TRIMMING DEVICE FOR POST SEWING MACHINES Filed June 2'?, 1962 2Sheets-Sheet 2 Fig.4

United States Patent O 3,176,639 G DEVICE FOR POST SEWING MACHINES sclaims. (ci. 112-123) The invention relates to trimming devices forsewingV machines and is particularly concerned with trimming devices forpost sewing machines of the type having a vertical looper shaft and arocking shaft disposed parallel to the looper shaft.

Trimming means are already known whose driving components are disposedwithin the cross-section of the post or pedestal of the machine.However, the known arrangements of this type are equipped with cuttersthat swing in vertical planes. Therefore, they can only be employed forsuch tailoring operations which start at the beginning of the work blankand are not interrupted during the sewing operation and are againcontinued.

lt is an object of the invention to arrange a material trimming deviceon post sewing machines having a cutter which swings in a horizontalplane in such a manner that a post of relatively small'cross-section canbe utilized. In accordance with the invention this is accomplished inthat the rocking shaft which is in the form of a hollow shaft isjournalled on the looper shaft. This provides for an extremely narrowpost in spite of the drive means for the trimmer being arranged withinthe post, so that it is possible, for example, to hang the uppers ofshoes over the post during the stitching and trimming of the heellining, thus substantially facilitating the execution of suchoperations.

It is of particular advantage to construct the trimming device in such amanner that a cutter carrier which extends from the rocking shaft to thetop side of the looper and laterally thereof carries a cutter which isarcuately shaped in a manner corresponding to the radius of its path ofoperation and swings about the axis of the looper. In this manner anoptimum post cross-section is achieved because, as viewed in the'direction of feed, the right side of the post becomes only negligiblywider than the diameter of the double stitch looper. The cutter whichswings about the axis of the looper is thus provided with a short leverarm so that vibrations are avoided to the greatest possible extentduring trimming operations.

It is a further objectV of the invention to form the looper closureplate in a manner that during operation the cutter swings above thelooper closure plate, while in inoperative position it is received in apart thereof which is raised and is provided with an entrance openingfor the cutter, thereby eliminating the cutter protector whichheretofore was normally required. The trimmer or cutter is thus receivedin the looper closure plate when it is inoperative so that on the onehand it is located in a position which is readily accessible for theoperator, while on the other hand catching or tangling of the thread onthe trimmer and cutting thereof is not possible even when the loops areloosely formed.

A structurally simple level adjusting means for the cutter or trimmer isobtained in that-an eccentric bolt carrying a sliding roller and whichcan be adjusted from the outside extends into a horizontal guide trackof the cutter support or carrier.

Further advantages and objects of the invention will become apparentfrom the following specification and by reference to the accompanyingdrawings which illustrate an embodiment of the invention and in which:

FIG. 1 is a front View of a sewing machine incorporating the invention;

FIG. 2 is a Section of the post of the machine taken from the front anddrawn to an enlarged scale;

FIG. 3 is a perspective view of the looper closure plate; and

FIG. 4 is a simplified perspective view of the driving mechanism.

As shown in FIG. 1, the machine comprises a base plate l, post 2, socket3, standard 4, arm 5 and machine head 6. The arm shaft 7 is journalledin the customary manner in the arm of the machine, and it is operativelyconnected at its forward end with a needle bar 9 which supports a needle8 and -is reciprocably movable in the machine head.

A pinion 10 is provided upon the arm shaft which, by way of a pinion 11,drives a shaft 12 arranged in the standard 4. At the lower end of thisshaft 12 a further pinion 13 is fastened, which by way of a counterpinion 14 passes on the driving force to a looper drive shaft 15 whichis horizontally journalled in the base plate 1. The shaft 1S supports apinion 16 at its forward end which meshes with a counter pinion 18mounted upon a vertical looper shaft 17 journalled in the post 2.

At the upper end of the looper shaft 17 a double stitch looper 19 isprovided which cooperates with the needle S and which is known per se.

Between two bearings 20, 21 of the looper shaft 17 a hollow shaftconstituting a rocking shaft 22 is rotatably mounted around the loopershaft 17. The rocking shaft 22, the axial movement of which is limitedby the upper side of the bearing 20 and by a collar 23 provided upon thelooper shaft 17, supports a crank 24 proximate its lower end to which adraw bar 25 is linked which, in turn, is operatively connected by way ofa drive mechanism. The drive mechanism for the rocking shaft 22 isaccommodated partly below the base plate 1 and partly in a housing Silsecured on top of said plate, and it comprises a draw bar 51encompassing an eccentric member 26 secured to the looper shaft 17. Theforward end of said draw bar 51 is pivotally supported upon a bolt 52. Alink 53 is secured to the bolt 52 below the draw bar 51, the free end ofwhich is pivotally supported upon a pivot member 54 which supports atits upper end one arm S5 of a bell crank lever 56, which is turn ispivotally supported by a pivot bolt 58. Arm 57 of the bell crank leveris linked to a draw bar 25 which is pivotally connected to a crank arm24 provided upon rocking shaft 22.

A further link member 59 is secured to the guided bolt 52 which isrotatably supported upon a shaft 60 and is provided with an arm 61 forvertically guiding the bolt 52. The arm 61 is slidable in a guide slot62 in the housing 50. rI'here is furthermore connected to the shaft 60 abell crank lever 63 having an arm 64 rotatably supported by means of apin 65 secured in the housing 50. The arm 66 of bell crank lever 63 hasa pin 67 which extends into a slot 68 of a setting disk 69. The settingdisk 69 is rotatably supported on a bolt 70 which is also secured to thehousing 5t) and which carries a setting lever 71 which is connected tothe pivot bolt 58. A further crank 27 is secured upon the rocking shaftwhich by way of a pin 29 received in a slot 2S is in operativeconnection with a cutter carrier or support 36 that is movablelongitudinally of the rocking shaft.

The cutter carrier 30 which extends laterally of the rocking shaft tothe upper side of the looper has a support member 32 which carries acutter or trimmer 31. The trimmer 31 which rocks about the looper shaft17 is arcuately shaped in a manner corresponding to its path f PatentedApr. 6, 1965 :savanne 3 of movement and is provided with an elongatedslot (not shown) so that the distance. `between needle 8 and the trimmer31 is adjustable within limits by means of a screw 33.

A looper closure cover 35 is pivotally mounted on the post 2 by means ofa hinge 34 with the top side 36 of the cover extending substantiallyparallel with respect to the rocking plate of the trimmer 31. Along theright side of the post as seen in the direction of feed, the loopercover 35 is bent upwardly and is provided at its rear portion with anaperture 37. Thus the double stitch looper and the elevated portion 38of the looper closure form an intermediate space 39 which receives thetrimmer. The trimmer in its operative position swings above thehorizontal upper side 36 of the looper cover, while in its position ofrest it is withdrawn through the aperture 37 and received in theintermediate space 39 and thus disappears completely below the loopercover.

Laterally of the post 2 an arrangement is provided for setting thecuttingk level or height of the trimmer. A bolt 41 journalled in thewall 40 of the post 2 is provided at one end with an eccentric lug 42.The lug 42 which mounts Va sliding roller 43 extends into a horizontalguide track 44 of the trimmer carrier or support 30. A setting lever 46is secured on the part 45 of the bolt 41 which extends from the post 2whereby the trimmer carrier 30 and thus the trimmer 31 can be raised andlowered in a manner corresponding to the eccentricity of the lug 42.

The trimmer 31 is moved fromitsinoperative position into operativeposition by rotating the setting lever 71, and its thrust is adjusted byrotating the setting disk 69. As this disk is rotated the pin 67 andthus the bell crank lever 63 are rotated about the pin 65, thus causingthe shaft 60 to move simultaneously about the pin 65, and in this mannerthe shaft 60 is moved to a position which is closer or further removedfrom the pivot member 54. The magnitude of the thrust of the cutter willcorrespond to the lateral distance of the shaftV 60 from the pivotmember 54. Y

As the looper shaft 17 isfrotated, the eccentric member Z6 impartsreciprocating movement to the bolt 52 by way of draw bar 51. At the sametime the link 59 effects a rocking movement about the rocking shaft 60causing link 53 to effect a rocking movement about the pivot member 54and in addition a movement in its longitudinal'direction whereby the arm55 of the bell crank lever 56 is rotated about the pivot bolt 58. As aresult also arm 57 swings about the pivot bolt 58 and effects therocking movement necessary forcutting or trimming by way of the draw barand crank 24.

i If the shaft 60 is swung by rotation of the setting disk 69 to such anextent that it is in alignment with the pivot member 54, then both links53, 59 rock about a common shaft 54, 6i), so that due to the sameeffective length of the two links no component of movementlongitudinally of the link 53 is developed, thus causing the bell cranklever 56 to remain inactive, and therefore cutter 31 stands still.

Having now described our invention with reference to the embodimentillustrated in the drawings, we do not We claim:

1. Trimming device for post sewing machine of the type having a looperprovided proximate and within the upper end of the work supporting post,said machine having a looper shaft supporting said looper and disposedin vertical positon in the post of the machine and a hollow rockingshaft journalled around said looper shaft, a trimmer carrierV supportedby said rocking shaft, a trimmer of arcuate conformation supported bysaid trimmer carrier and movable with said carrier about the axis ofsaid looper shaft, said trimmer carrier having a horizontally disposedguide track, and a bolt having a setting lever mounted externally ofsaid post and supported by said post having an eccentric memberextending into said track.

2. Trimming device for post sewing machine of the type having a looperprovided proximate land within the upper end of the work supportingpost, said machine having a looper shaft supporting said looper anddisposed in vertical positon in the post of the machine and a hollowrocking shaft journalled around said looper shaft, a trimmer carriersupported by said rocking shaft, a trimmer of arcuate conformationsupported by said trimmer carrier and movable with said carrier aboutthe axis of said looper shaft, said post having a looper coverpresenting an elevated portion and a horizontal surface at a lower levelthan said elevated portion, said elevated portion defining an apertureproximate said horizontal surface for permitting movement of saidtrimmer therethrough and to receive said trimmer while in inoperativecondition.

3. Trimming device for post sewing machine of the type having a looperprovided proximate and within the upper end of the work supporting post,saidrmachine having a looper shaft supporting said looper and disposedin vertical positon in the post of the machine and a hollow rockingshaft journalled around said looper shaft, a trimmer carrier supportedby said rocking shaft, a trimmer of arcuate conformation supported bysaid trimmer carrier and movable with said carrier about the axis ofsaid looper shaft, said trimmer carrier having a horizontally disposedguide track, and a bolt having a setting lever mounted externally ofsaid post and supported by said post having an eccentric memberextending into said track, said post having a looper cover presenting anelevated portion and a horizontal surface at a lower level than saidelevated portion, said elevated portion and said horizontal surfacedefining an aperture therebetween for permitting horizontal movement ofsaid trimmer therethrough.

References Cited-by the Examiner UNITED STATES PATENTS 1,401,973 l/22Fifeld 112-252 1,883,654 lO/32 Ericsson 112-252 2,903,233 9/59 Magor74-50 X FOREIGN PATENTS 499,292 l/ 39 Great Britain.

JORDAN FRANKLIN, Prmmy Examiner.

DAVID J. WILLIAMOWSKY, ROBERT V. SLOAN,

Examiners.

1. TRIMMING DEVICE FOR POST SEWING MACHINE OF THE TYPE HAVING A LOOPERPROVIDED PROXIMATE AND WITHIN THE UPPER END OF THE WORK SUPPORTING POST,SAID MACHINE HAVING A LOOPER SHAFT SUPPORTING SAID LOOPER AND DISPOSEDIN VERTICAL POSITION IN THE POST OF THE MACHINE AND A HOLLOW ROCKINGSHAFT JOURNALLED AROUND SAID LOPER SHAFT, A TRIMMER CARRIER SUPPORTED BYSAID ROCKING SHAFT, A TRIMMER OF ARCUATE CONFORMATION SUPPORTED BY SAID